I am not a vegetarian. Usually cottage pie is made from mince. I swapped mince for quorn mince to see if it tasted good. However, it can be a little bland, so to make it mighty meaty in taste, despite being a vegetarian favourite, I actually soaked the quorn mince in some beef stock.
This was my attempt. The potato didn't spread too well, but trust me, it tasted lovely. Obviously if you are a vegetarian, you wouldn't use the beef stock, but if you are a veggie, then you wouldn't be needing to make this particular small change anyway!
For me, being quite a lover of cottage pie, I wasn't at all sure. I can't say it will be a permanent swap, but the idea is to make one small change. If you can swap it once and cut out all those calories then it will add up over time.
Give it a go and let me know what you think of a quorn cottage pie. :)